The catalytic properties of nanoparticle catalysts, especially supported metal nanoparticle catalysts, depend on their size, shape, surface structure, and interactions with the support material. During a catalytic reaction, the catalytically active nanoparticles interact with different types of molecules (reactant, intermediate and product molecules), often at elevated temperatures.  Such molecular interactions can exert significant influence, particularly for small nanoparticles or clusters, on their shape, surface structure and stability. To better correlate the observed nano- and atomic-scale structures to the performance of a nanostructured catalyst, it is highly desirable and, in some cases, imperative to characterize the catalysts of interest by in situ techniques.  Atomic resolution environmental electron microscopy (EM) and associated techniques, especially with the incorporation of aberration correctors, either operated in the transmission or scanning transmission mode, can provide critical information on the dynamic behavior of nanostructured catalysts under gas environment, with �ngstr�m level resolution, and at elevated temperatures. Incorporation of other in situ probes such as UV-visible illumination significantly expands the applications of atomic resolution environmental EM techniques. Surface atomic rearrangements of supported metal (e.g., Au) nanoparticles in response to different gases at elevated temperatures shed light on the dynamic behavior of supported metal catalysts and provide valuable information on understanding the catalytic performance and stability of supported metal nanoparticles, clusters, or even single atoms.

Atomic resolution environmental electron microscopy of the dynamic behavior of supported metal catalysts

248th National Meeting (2014)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.